<PAGE>

                                                                    Exhibit 10.3

                               AMENDMENT NO. 3 TO
                  AMENDED AND RESTATED REVOLVING LOAN AGREEMENT

            THIS AMENDMENT NO. 3 TO AMENDED AND RESTATED REVOLVING LOAN
AGREEMENT (this "Amendment"), dated as of August 12, 2003, is entered into by
and among the financial institutions listed on the signature pages hereof
(individually, a "Lender" and collectively, the "Lenders"), Union Bank of
California, N.A., as Administrative Agent (in such capacity, the "Administrative
Agent"), Comerica Bank (formerly Comerica Bank-California), as Collateral Agent,
and ViaSat, Inc., a Delaware corporation (the "Borrower"), with reference to the
following facts:

                                    RECITALS

The Borrower, the Lenders, the Administrative Agent and the Collateral Agent are
parties to the Amended and Restated Revolving Loan Agreement, dated as of
December 31, 2002, as amended (the "Loan Agreement"), pursuant to which the
Lenders have provided the Borrower with a Revolving Loan facility and a
subfacility for Letters of Credit.

The parties wish to amend the Loan Agreement as set forth below.

                                    AGREEMENT

            NOW, THEREFORE, the parties hereby agree as follows:

      1. Defined Terms. Any and all initially capitalized terms used in this
Amendment (including, without limitation, in the recitals hereto) without
definition shall have the respective meanings specified in the Loan Agreement.

      2. New Grid Pricing Definitions. Section 1.1 of the Loan Agreement is
hereby amended and supplemented by adding the following new definitions in
appropriate alphabetical order:

            "'Applicable Base Rate Margin' means, for each Pricing Period, the
            interest rate margin set forth below (expressed in basis points per
            annum) opposite the Applicable Pricing Level for that Pricing
            Period:

                         Applicable               Margin
                       Pricing Level

                             I                        0

                             II                      25

                            III                      50

                                      -1-
<PAGE>
            'Applicable Commitment Fee Rate' means, for each Pricing Period, the
            rate set forth below (expressed in basis points per annum) opposite
            the Applicable Pricing Level for that Pricing Period:

                                 Commitment Fee

                         Applicable
                       Pricing Level

                             I                       25

                             II                      37.5

                            III                      50


            'Applicable Eurodollar Rate Margin' means, for each Pricing Period,
            the interest rate margin set forth below (expressed in basis points
            per annum) opposite the Applicable Pricing Level for that Pricing
            Period:

                         Applicable
                       Pricing Level              Margin
                             I                      175

                             II                     200

                            III                     225


            'Applicable Pricing Level' means, for each Pricing Period, the
            pricing level set forth below opposite the Leverage Ratio as of the
            last day of the Fiscal Quarter most recently ended prior to the
            commencement of that Pricing Period:

                       Pricing Level        Leverage Ratio
                             I           Less than 1.00 to 1.00

                             II          Greater than or equal to 1.00 to
                                         1.00, but less than 1.50 to 1.00

                            III          Greater than or equal to 1.50 to 1.00


            provided that (i) in the event that Borrower does not deliver a
            Pricing Certificate to the Administrative Agent with respect to any
            Pricing Period prior to the commencement of such Pricing Period,
            then until such Pricing


                                      -2-
<PAGE>
            Certificate is delivered to the Administrative Agent, the Applicable
            Pricing Level for that Pricing Period shall be Pricing Level III,
            but once Borrower has delivered a Pricing Certificate with respect
            to such Pricing Period, then any resulting change in the Applicable
            Pricing Level shall be made retroactively to the beginning of such
            Pricing Period, and (ii) if any Pricing Certificate is subsequently
            determined to be in error, then any resulting change in the
            Applicable Pricing Level shall be made retroactively to the
            beginning of the relevant Pricing Period.

            'Pricing Certificate' means a certificate in the form of Exhibit K,
            properly completed and signed by a Senior Officer or his or her
            designated representative of Borrower.

            'Pricing Period' means (a) the period commencing on August 16, 2003
            and ending on November 17, 2003, (b) the period commencing on
            November 18, 2003 and ending on February 16, 2003, and (c)
            thereafter the period commencing on each May 19, August 18, November
            17 and February 16 and ending on the next following August 17,
            November 16, February 15, or May 18, respectively. "

      3. Amendment to Commitment: Section 1.1 of the Loan Agreement is hereby
amended such that the definition of "Commitment" set forth therein is amended to
read in full as follows:

            "`Commitment' means, subject to Section 2.5, $30,000,000. The
            respective Pro Rata Shares of the Lenders with respect to the
            Commitment are set forth in Schedule 1.1."

      4. Amendment to Commitment: Section 1.1 of the Loan Agreement is hereby
amended such that the definition of "EBITDA" set forth therein is amended to
read in full as follows:

            "'EBITDA' means, with respect to any fiscal period and with respect
to Borrower and its Subsidiaries on a consolidated basis, the sum of (a) income
from operations as set forth on the Borrower's GAAP statement of operation, plus
(b) depreciation, plus (c) amortization (without duplication)."

      5. Amendment to Revolving Loan Maturity Date: Section 1.1 of the Loan
Agreement is hereby amended such that the definition of "Revolving Loan Maturity
Date" set forth therein is amended to read in full as follows:

            "'Revolving Loan Maturity Date' means September 30, 2004."

      6. Amendment to Letters of Credit. Section 2.4(a) of the Loan Agreement is
hereby amended to read in full as follows:

                                      -3-
<PAGE>
            "(a) The Existing Letters of Credit described in Schedule 2.4 shall
            be Letters of Credit for all purposes under this Agreement.

                  (1)   Subject to the terms and conditions hereof, at any time
                        and from time to time from the Closing Date through the
                        Revolving Loan Maturity Date, the Issuing Lender shall
                        issue such Letters of Credit under the Commitment as
                        Borrower may request by a Request for Letter of Credit;
                        provided that:

                        (i) giving effect to all such Letters of Credit, the sum
                        of:

                              (A)   the aggregate principal amount outstanding
                                    under the Revolving Notes; plus

                              (B)   the Aggregate Effective Amount of all
                                    outstanding Letters of Credit, does not
                                    exceed the then applicable Commitment; and

                        (ii) the Aggregate Effective Amount under all
                        outstanding Letters of Credit does not exceed
                        $10,000,000.

                  (2)   Each Letter of Credit shall be in a form reasonably
                        acceptable to the Issuing Lender.

                  (3)   Unless all the Lenders otherwise consent in a writing
                        delivered to the Administrative Agent, the term of any
                        Letter of Credit (other than any Existing Letters of
                        Credit) shall not exceed one (1) year.

                  (4)   The term of any Letter of Credit (other than any
                        Existing Letters of Credit) shall not extend one hundred
                        eighty (180) days beyond the Revolving Loan Maturity
                        Date unless:

                        i)    all the Lenders otherwise consent in a writing
                              delivered to the Administrative Agent;

                        ii)the Borrower provides the Issuing Lender with cash
                              collateral in the amount equal to 100% of the face
                              amount of the Requested Letter of Credit (or such
                              lesser amount as shall then be available for
                              drawing under the Requested Letter of Credit); or

                        iii)  the Borrower provides the Issuing Lender with a
                              "back-up" standby letter of credit in the full
                              face amount of the Requested Letter of Credit (or
                              such lesser amount as shall then be available
                              under the Requested Letter of Credit) issued by a
                              bank acceptable to the Issuing Bank in its
                              reasonable discretion.



                                      -4-
<PAGE>
      7. Amendment to Base Rate Interest Rate Provision. Section 3.1(b) is
hereby amended to read in full as follows:

            "(b) Interest accrued on each Base Rate Loan shall be due and
            payable on each Monthly Payment Date. Except as otherwise provided
            in Sections 3.1(d) and 3.8, the unpaid principal amount of any Base
            Rate Loan shall bear interest at a fluctuating rate per annum equal
            to the Base Rate plus the Applicable Base Rate Margin. Each change
            in the interest rate under this Section 3.1(b) due to a change in
            the Base Rate shall take effect simultaneously with the
            corresponding change in the Base Rate."

      8. Amendment to Eurodollar Rate Interest Rate Provision. Section 3.1(c) is
hereby amended to read in full as follows:

            "(c) Interest accrued on each Eurodollar Rate Loan shall be due and
            payable on the last day of the related Eurodollar Period. Except as
            otherwise provided in Sections 3.1(d) and 3.8, the unpaid principal
            amount of any Eurodollar Rate Loan shall bear interest at a rate per
            annum equal to the Eurodollar Rate for that Eurodollar Rate Loan
            plus the Applicable Eurodollar Rate Margin."

      9. Amendment to Commitment Fee. Section 3.3 is hereby amended to read in
full as follows:

            " 3.3 Commitment Fee. From the Closing Date through the Revolving
            Loan Maturity Date, Borrower shall pay to the Administrative Agent,
            for the ratable accounts of the Lenders pro rata according to their
            Pro Rata Share of the Revolving Commitment, a commitment fee equal
            to the Applicable Commitment Fee Rate per annum times the average
            daily amount by which the Commitment exceeds the (i) aggregate daily
            principal Indebtedness evidenced by the Revolving Notes plus (ii)
            the Aggregate Effective Amount of all Letters of Credit then
            outstanding. The commitment fee shall be payable quarterly in
            arrears as of each Quarterly Payment Date within ten (10) days after
            receipt by Borrower of an invoice therefor from the Administrative
            Agent."

      10. Amendment to Letter of Credit Fee. Section 3.4(a) is hereby amended to
read in full as follows:

            "(a) concurrently with the issuance of each Standby Letter of
            Credit, to the Administrative Agent a standby letter of credit fee
            in an amount equal to the Applicable Eurodollar Margin per annum
            times the face amount of such Standby Letter of Credit through the
            termination or expiration of such Standby Letter of Credit, the
            first 10% of which fee the Administrative Agent shall promptly pay
            to UBOC and the remainder of which fee the Administrative Agent
            shall promptly pay to the Lenders


                                      -5-
<PAGE>
            ratably, in accordance with their respective Pro Rata Shares of the
            Commitment;"

      11. Amendment to Eurodollar Prepayment Fee. Section 3.6(e)(2) is hereby
amended to read in full as follows:

            "(e)(2) the amount, if any, by which (i) the additional interest
            would have accrued on the amount prepaid or not borrowed at the
            Eurodollar Rate plus the Applicable Eurodollar Rate Margin if that
            amount had remained or been outstanding through the last day of the
            applicable Eurodollar Period exceeds (ii) the interest that the
            Lender could recover by placing such amount on deposit in the
            Designated Eurodollar Market for a period beginning on the date of
            the prepayment or failure to borrow and ending on the last day of
            the applicable Eurodollar Period (or, if no deposit rate quotation
            is available for such period, for the most comparable period for
            which a deposit rate quotation may be obtained); plus"

      12. Amendment to Minimum EBITDA Covenant. Section 6.13 of the Loan
Agreement is hereby amended to read in full as follows:

            "6.13 EBITDA. Permit EBITDA for any Fiscal Quarter of Borrower to be
            less than $4,000,000."

      13. Delivery of Pricing Certificate. Section 7.1(b) of the Loan Agreement
is hereby amended to read in full as follows:

            "(b) As soon as practicable, and in any event within 45 days after
            the end of each Fiscal Quarter, a Pricing Certificate setting forth
            a calculation of the Leverage Ratio as of the last day of such
            Fiscal Quarter, and providing reasonable detail as to the
            calculation thereof, which calculations in the case of the fourth
            Fiscal Quarter in any Fiscal Year shall be based on the preliminary
            unaudited financial statements of Borrower and its Subsidiaries for
            such Fiscal Quarter, and as soon as practicable thereafter, in the
            event of any material variance in the actual calculation of the
            Leverage Ratio from such preliminary calculation, a revised Pricing
            Certificate setting forth the actual calculation thereof;"

      14. Amendment to Schedule of Commitments. Schedule 1.1 to the Loan
Agreement is hereby amended and replaced by Schedule 1.1 to this Amendment.

      15. New Pricing Certificate. The Loan Agreement is hereby further amended
and supplemented by adding a new Exhibit K thereto in the form of Exhibit K to
this Amendment. Borrower represents and warrants that Borrower will deliver a
completed Pricing Certificate no later than August 15, 2003 with regard to the
pricing period ended June 30, 2003.

      16. Amendment Fee. In consideration of the Lenders' agreement to enter
into this Amendment and provide the Borrower with the accommodations described
herein, on the


                                      -6-
<PAGE>
            effective date of this Amendment, the Borrower shall pay to the
            Administrative Agent, for the ratable benefit of the Lenders, a
            one-time fee of $30,000 (the "Amendment Fee"). The Borrower
            acknowledges and agrees that, at the Administrative Agent's option,
            the Administrative Agent may effect payment of the Amendment Fee by
            charging the full amount of such fee, when due, to the Borrower's
            Revolving Loan account or to the Borrower's checking account at
            Union Bank of California, N.A.

      17. Condition Precedent. The effectiveness of this Amendment shall be
subject to the prior satisfaction of each of the following conditions:

            (b)   This Amendment. The Agent shall have received an original of
                  this Amendment, duly executed by the Borrower and each of the
                  Lenders;

            (c)   Certificate. The Assistant Secretary of Borrower shall have
                  executed the Certificate of Resolution attached to this
                  Amendment;

            (d)   Revolving Note to Union Bank. Borrower shall have executed a
                  Revolving Note, in the original principal amount of
                  $15,00,000, to the order of Union Bank of California, N.A;

            (e)   Revolving Note to Comerica Bank. Borrower shall have executed
                  a Revolving Note, in the original principal amount of
                  $15,00,000, to the order of Comerica Bank - California;

            (f)   Other Documents. The Borrower shall have executed and
                  delivered to the Agent such other documents and instruments as
                  the Agent may reasonably require.

      18. Miscellaneous.

            (a)   Survival of Representations and Warranties. All
                  representations and warranties made in the Loan Agreement or
                  in any other document or documents relating thereto,
                  including, without limitation, any Loan Document furnished in
                  connection with this Amendment, shall survive the execution
                  and delivery of this Amendment and the other Loan Documents,
                  and no investigation by the Administrative Agent or the
                  Lenders or any closing shall affect the representations and
                  warranties or the right of the Administrative Agent or any
                  Lender to rely thereon.

            (b)   No Events of Default. The Borrower is not aware of any events
                  which now constitute, or with the passage of time or the
                  giving of notice, or both, would constitute, an Event of
                  Default under the Loan Agreement.

            (c)   Reference to Loan Agreement. The Loan Agreement, each of the
                  other Loan Documents, and any and all other agreements,

                                      -7-
<PAGE>
                  documents or instruments now or hereafter executed and
                  delivered pursuant to the terms hereof, or pursuant to the
                  terms of the Loan Agreement as amended hereby, are hereby
                  amended so that any reference therein to the Loan Agreement
                  shall mean a reference to the Loan Agreement as amended
                  hereby.

            (d)   Loan Agreement Remains in Effect. The Loan Agreement and the
                  other Loan Documents remain in full force and effect and the
                  Borrower ratifies and confirms its agreements and covenants
                  contained therein. The Borrower hereby confirms that, after
                  giving effect to this Amendment, no Event of Default or
                  Default exists as of such date.

            (e)   Severability. Any provision of this Amendment held by a court
                  of competent jurisdiction to be invalid or unenforceable shall
                  not impair or invalidate the remainder of this Amendment and
                  the effect thereof shall be confined to the provision so held
                  to be invalid or unenforceable.

            (f)   APPLICABLE LAW. THIS AMENDMENT AND ALL OTHER LOAN DOCUMENTS
                  EXECUTED PURSUANT HERETO SHALL BE DEEMED TO HAVE BEEN MADE AND
                  TO BE PERFORMABLE IN THE STATE OF CALIFORNIA AND SHALL BE
                  GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE
                  STATE OF CALIFORNIA.

            (g)   Successors and Assigns. This Amendment is binding upon and
                  shall inure to the benefit of the Lenders and the Borrower and
                  their respective successors and assigns; provided, however,
                  that the Borrower may not assign or transfer any of its rights
                  or obligations hereunder without the prior written consent of
                  the Lenders.

            (h)   Counterparts. This Amendment may be executed in one or more
                  counterparts, each of which when so executed shall be deemed
                  to be an original, but all of which when taken together shall
                  constitute one and the same instrument.

            (i)   Headings. The headings, captions and arrangements used in this
                  Amendment are for convenience only and shall not affect the
                  interpretation of this Amendment.

            (j)   NO ORAL AGREEMENTS. THIS AMENDMENT, TOGETHER WITH THE OTHER
                  LOAN DOCUMENTS AS WRITTEN, REPRESENTS THE FINAL AGREEMENT
                  BETWEEN THE LENDERS AND THE BORROWER AND MAY NOT BE
                  CONTRADICTED BY EVIDENCE OF PRIOR,


                                      -8-
<PAGE>
                  CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES.
                  THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE LENDERS AND
                  THE BORROWER.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]



                                      -9-
<PAGE>
      IN WITNESS WHEREOF, the parties have entered into this Amendment by their
      respective duly authorized officers as of the date first above written.

                                              VIASAT, INC.

                                              By:____________________________
                                                       Ronald G. Wangerin
                                                       Vice President and Chief
                                                       Financial Officer

                                              UNION BANK OF CALIFORNIA, N.A.,
                                              as the Administrative Agent


                                              By:____________________________
                                                       Douglas S. Lambell
                                                       Vice President

                                              COMERICA BANK-CALIFORNIA,
                                              as the Collateral Agent

                                              By: _____________________________
                                                       Stephen M. Cusato
                                                       Senior Vice President

                                              UNION BANK OF CALIFORNIA, N.A.,
                                              as a Lender


                                              By:____________________________
                                                       Douglas S. Lambell
                                                       Vice President

                                              COMERICA BANK - CALIFORNIA,
                                              as a Lender

                                              By:____________________________
                                                       Stephen M. Cusato
                                                       Senior Vice President



                                      -10-
<PAGE>
                                  SCHEDULE 1.1

                               LENDER COMMITMENTS

<TABLE>
<CAPTION>
                                        Revolving Commitment Amount                 Pro Rata Share
<S>                                     <C>                                         <C>
UNION BANK OF CALIFORNIA, N.A.                  $15,000,000                               50%
COMERICA BANK                                   $15,000,000                               50%
                                                ===========                               ===
Total:                                          $30,000,000                               100%

</TABLE>



                                      -11-
<PAGE>
                                    EXHIBIT K

                               PRICING CERTIFICATE

           TO: UNION BANK OF CALIFORNIA, N.A., as Administrative Agent


            Reference is made to the Amended and Restated Revolving Loan
Agreement, dated as of December 31, 2002, as amended (the "Loan Agreement"), by
and among ViaSat, Inc., a Delaware corporation ("Borrower"), the Lenders therein
named, Comerica Bank, as Collateral Agent for the Lenders, Union Bank of
California, N.A., as Administrative Agent for the Lenders. Capitalized terms
defined in the Loan Agreement and not otherwise defined herein shall have the
meanings given them in the Loan Agreement.

            This Pricing Certificate (this "Certificate") is delivered in
accordance with Section 7.1(b) of the Loan Agreement by a Senior Officer of
Borrower with respect to the Pricing Period commencing ___________, ____, and
ending on _____________, ____ (the "Subject Pricing Period"). Computations used
to determine the Applicable Pricing Level for the Subject Pricing Period are set
forth below:

      I. APPLICABLE PRICING LEVEL. Subject to later adjustment as provided in
      the Loan Agreement, the Applicable Pricing Level for the Subject Pricing
      Period shall be Level ______1.


The Applicable Pricing Level set forth above was determined on the basis of the
following:

      LEVERAGE RATIO. As of the last day (the "Determination Date") of the
Fiscal Quarter ended ____________ (the "Test Fiscal Quarter"), the Leverage
Ratio was _____ : 1.00 (as calculated below).

      LEVERAGE RATIO - Calculation:


<TABLE>
<S>                                                                                         <C>
(a)  all Indebtedness of Borrower and its Subsidiaries on the Determination Date            $_________

divided by

(b) EBITDA for the fiscal period consisting of the four (4) Fiscal Quarters ended on the    $_________
     Determination Date (as calculated below)
</TABLE>


--------
1     Insert Level I, II, III, IV or V in accordance with the terms of the Loan
      Agreement based upon the determination of the Leverage Ratio.



                                      -12-
<PAGE>
<TABLE>
<S>                                                                                         <C>
equals Leverage Ratio [(a)/(b)]                                                             ______:1.00


         EBITDA - Component Calculations

(a) Net Income from operations                                                              $_________

plus

(e) depreciation                                                                            $_________

plus

(f) amortization                                                                            $_________

Equals EBITDA [(a)+(b)+(c)]                                                                 $_________
</TABLE>


            II. I further certify that the calculations made and the information
contained herein are derived from the books and records of Borrower and its
Subsidiaries, as applicable, and that to the best of my knowledge, in my
capacity as a Senior Officer of Borrower, each and every matter correctly
reflects those books and records.

            IN WITNESS WHEREOF, I have signed this Pricing Certificate on this
_______ day of __________, ____.




------------------------------------

------------------------------------
      [Printed Name and Title of Senior
                       Officer of ViaSat, Inc.]



                                      -13-